Dryer appliances generally include a cabinet with a drum mounted therein. In many dryer appliances, a motor rotates the drum during operation of the dryer appliance, e.g., to tumble articles located within a chamber defined by the drum. Alternatively, dryer appliances with fixed drums have been utilized. Dryer appliances also generally include a heater assembly that passes heated air through the chamber of the drum in order to dry moisture-laden articles disposed within the chamber. This internal air then passes from the chamber through a vent duct to an exhaust conduit, through which the air is exhausted from the dryer appliance. Typically, an air handler or blower is utilized to flow the internal air from the vent duct to the exhaust duct. When operating, the blower may pull air through itself from the vent duct, and this air may then flow from the blower to the exhaust conduit.
Although dryer appliances often include filter systems to prevent foreign materials, such as lint, from passing into the exhaust conduit, it is difficult for such systems to prevent all foreign materials from entering the exhaust conduit. Although lint may be driven from the exhaust while the blower is operating, suspended lint may fall and rest within the exhaust once the blower ceases to operate. If permitted to accumulate within the exhaust conduit, such foreign materials may impair dryer performance. For instance, accumulated lint may restrict the effective operating size of the passages through which air flows during operation. Restrictions can prevent proper airflow, thereby hindering drying of articles. In more severe cases, the collection of lint may present a fire hazard due to the potential for combustion.
Accordingly, improved dryer appliances and methods for detecting venting blockages are desirable. More particularly, dryer appliances including simple, cost effective, and reliable means for detecting clogs would be particularly beneficial.